n 1 : weariness or exhaustion from labor, exertion, or stress 2 : the temporary loss of power to respond induced in a sensory receptor or motor end organ by continued stimulation vb, fa*tiguedfa*tigu*ingvt 1 : to weary with labor or exertion 2 : to induce a condition of fatigue in (as an effector organ) vi : to be affected with fatigue : become weary .